Abstract: Bipolar disorder (BD) is a serious, disabling, and highly recurrent illness that is disproportionately represented in the criminal justice system. BD increases risk for several adverse outcomes for prisoners, including mood instability, suicide attempts, substance use relapse, and high rates of repeat incarceration. Despite these serious negative sequelae, up to 70% of prisoners with BD do not receive mental health treatment upon prison release. Lack of engagement in ongoing mental health treatment for BD upon community re-entry represents one potent factor that perpetuates risk for adverse outcomes, and consequences of untreated BD (e.g., impulsivity, substance use) may greatly exacerbate difficulties in establishing stable living conditions (e.g., adequate housing, legal employment) at community re-entry. Thus, there is a critical need for interventions to facilitate engagement with treatment for BD during this vulnerable transition. The primary aim of this R34 pilot effectiveness trial (RFA-MH-17-612) is to develop and establish the feasibility, acceptability, and potential for future uptake of the Community treatment Adherence at Re-Entry (CARE) program. CARE is an innovative intervention that combines evidence-based cognitive-behavioral, family, and telephone outreach strategies to promote treatment engagement and improve clinical outcomes for prisoners with BD during the period of community re-entry. Informed by our pilot work, CARE will include 3 individual and 1 family session in prison, followed by 11 brief telephone contacts for up to 6 months post-release. Given its moderate intensity, adjunctive nature, use of community mental health counselors, and telephone administration, CARE has been designed with an eye toward community implementation. Its mechanisms of action (i.e., increasing values- action consistency, enhancing social supports, and service linkage, all to promote treatment engagement, thereby improving clinical outcomes) are further well matched to the practical and clinical needs of re-entering individuals. The development phase of the study will result in a treatment manual, training manual, and fidelity scales, to be tested in an open trial of 12 prisoners with BD nearing prison release. The pilot study will examine feasibility and acceptability of the proposed recruitment methods, research design, intervention, and training program by randomizing 40 prisoners with BD nearing prison release to treatment as usual (TAU), enhanced with monitoring and emergency referral, or to enhanced TAU plus CARE. The primary outcome will be mood symptoms in the 6 months post-release. Secondary outcomes include: suicidal ideation/behaviors, substance use, re-arrest rates, and employment and housing stability. We will also explore differential engagement of CARE?s purported mechanisms of action. To our knowledge, this proposal represents the first attempt to develop and pilot a targeted transitional interventional for BD among prisoners, laying the groundwork for a larger clinical trial (R01) to evaluate the effectiveness of CARE for improving clinical outcomes for this seriously ill, high risk, understudied population during the vulnerable transition from prison to community re-entry.